1. Field of the Invention
The present invention relates to an image sensing apparatus, and an optical touch control apparatus and a motion tracking apparatus utilizing the image sensing apparatus, and particularly relates to an image sensing apparatus, and an optical touch control apparatus and a motion tracking apparatus, which can change a size of an image sensing region.
2. Description of the Prior Art
In the prior art, a sensing region of an image sensor is fixed. For example, a total image sensing region of the image sensor is utilized to sense an image. However, such mechanism consumes large power and wrong image might be detected. FIG. 1 is a schematic diagram illustrating how a prior art image sensor utilizes a total image sensing region to sense an image. As shown in FIG. 1, the image sensor 100 utilizes all sensing region of the image sensor (i.e. a total image sensing region, a matrix with M×N pixels in this example) to sense an image. However, the image sensor may have a disturbance region P caused by dust or dirt, such that the image sensed by the image sensor 100 may include an image caused by the disturbance region P. Therefore, a wrong image is sensed.